A team of researchers in the Mato Grosso region of Brazil has uncovered a set of resonant stone bars, or lithophones, coated in a rare 'hematite-lacquer.' Radiocarbon dating of associated organic material places these musical instruments at the end of the Pleistocene, roughly 12,000 years ago. The lithophones were found in a cave system known for its acoustic properties, which the researchers believe served as a cathedral for 'Spirit-Rain' festivals during the transition to the wet season.
The hematite coating not only provided a deep reddish hue to the stones but also appears to have been applied to alter their vibratory frequency. When struck, the stones produce a haunting, metallic tone that echoes throughout the cavern. The site also contains several rock art panels depicting figures in dynamic poses, which archaeologists interpret as the earliest pictorial representations of communal dance and rhythmic ritual in the Amazon basin.